Final Project

Pre-Covid American Dietary Intention and B Vitamins
Author

Giuliet Kibler

This project reviews the dietary intake over the 24-hour period prior to the interview of Americans 1 year or older between 2017 and March of 2020, as collected in the National Health and Nutrition Examination Survey. This data set includes dietary information from the first interview and is a log of the total energy and nutrient intakes, including the macronutrients (carbohydrates, fats, and proteins) and vitamins, from foods and beverages within the previous 24-hours. The project analyzes whether participants intended diet (macronutrient dietary intention) aligns with their actual food consumption (dietary intake). Additionally, it assesses the relationship between dietary intake and the B vitamins intake. B vitamins are cofactors for many cellular pathways, including cellular metabolism and synthesis of DNA and RNA, but are not stored by the body, so it is critical to replenish them daily through foods and supplements (Hanna et al, 2022). Therefore, this analysis is to assess if Americans 1 year or older are eating their intended macronutrient diet and if their intake is associated with B vitamin levels pre-pandemic (January 2017-March 2020).

Distribution of macronutrient intake by diet type

The low sugar group averaged lower total sugars than those not on the diet (62.24 vs 90.89 g). Additionally, the low carbohydrate group ate less carbohydrates than those not on this diet (165.395 vs 219.08 g). On the other hand, those on a low fat diet ate more fats than those not on the diet (72.62 vs 71.805 g), meaning the average participant on a low fat diet did not eat less fats than other participants. The average high protein diet had substantially more protein intake than those not on the diet (100.61 vs 64.72 g). Therefore, participants on a low sugar, low carbohydrate, or high protein diet stuck to their diet, while those on a low fat diet did not.

Distribution of caloric intake

The median high calorie diet included substantially higher caloric intake than either the low calorie diet or those not on a caloric diet (2528 vs 1834 and 1821 cals, respectively), meaning participants intending to eat high amounts of calories are following their dietary plan. On the other hand, the low calorie diet had a slightly higher median than those not on a caloric diet (1834 vs 1821 cals), meaning the average participant on a low calorie diet actually ate more calories than those not intending to calorically restrict and were not following their intended diet.

Association between B vitamins and nutritional intake

Linear regressions are fit for each of the analyzed diets to answer the question of whether macronutrient consumption is correlated with B vitamin intake. B1 and B2 vitamins are more strongly associated (highest correlation value of 0.32 to 0.48 and 0.31 to 0.42, respectively) with all of the macronutrient intakes than B6 (correlation of 0.14 to 0.28). The highest correlations occur between B1 and caloric intake (0.48) and B1 and carbohydrate intake (0.45). Overall, this demonstrates that getting enough dietary nutrition is critical for B1 and B2 vitamin daily replenishment.

Red dashed lines are used to represent the recommended B vitamin intake levels for men of 1.2 mg of B1, 1.3 milligrams (mg) of B2 and 1.0 mg of B6.

Association between caloric diet and B vitamin levels

Given that caloric intake is correlated with B vitamin levels, it is useful to know if caloric intake is also associated with B vitamin levels each caloric diet group.

Overall, B vitamins have a mild-to-moderate association with dietary intake. The high calorie diet in the graphs of vitamins B1 and B2 vs calories have the highest slopes, indicating that an intention to eat more calories is also associated with an increase in B vitamin intake. This finding makes sense given participants on a high calorie diet actually eat more calories and caloric intake was shown to be moderately associated with these B vitamin levels. Interestingly, caloric diet type’s association with the B vitamins was not consistent between the vitamins, indicating that more than just dietary intention is necessary for sufficient B vitamin intake.